diff --git a/app/controllers/application_controller.rb b/app/controllers/application_controller.rb
index 8323528ce47..f02c9c97595 100644
--- a/app/controllers/application_controller.rb
+++ b/app/controllers/application_controller.rb
@@ -156,7 +156,7 @@ class ApplicationController < ActionController::Base
   end
 
   rescue_from Discourse::ReadOnly do
-    render_json_error I18n.t('read_only_mode_enabled'), type: :read_only, status: 405
+    render_json_error I18n.t('read_only_mode_enabled'), type: :read_only, status: 503
   end
 
   def rescue_discourse_actions(type, status_code, include_ember=false)